Question #42234

1 Answer
Feb 18, 2018

29.8ml

Explanation:

Density of liquid oxygen = 1.141g/cm^3
Density of liquid hydrogen = 0.071 g/cm^3

Since 1ml=1cm^3 and density = (mass)/(volume) we can calculate the masses of the above:
Mass oxygen=1.141times10=11.41g
Mass hydrogen= 0.071 times 50=3.55g

We can calculate relative molecualr masses (I have used 1d.p. but you may wish to be more accurate)
Mr (O_2)=16.0 times2=32.0
Mr (H_2)=1.0times2=2.0

We can now work out the number of moles of each:
Moles (O_2)=11.41/32.0=0.357 mol

Moles (H_2)=3.55/2.0=1.775 mol

The reaction is
2H_2 +O_2 to 2H_2O

so 2 moles H_2 reacts with 1 mole O_2
hence unreacted H_2 = 1.775-(0.357times2)=1.061mol

And so Mass = 1.061 times 2= 2.122g

and volume = 2.122/0.071=29.9ml